Performance tweak: use vector for effects and potentials

Author: liufengyun

compiler/src/dotty/tools/dotc/transform/init/Checking.scala

@@ -326,14 +326,14 @@ object Checking {
 
           case Fun(pots, effs) =>
             val name = sym.name.toString
-            if (name == "apply") Summary(pots, Effects.empty)
-            else if (name == "tupled") Summary(Set(pot1), Effects.empty)
+            if (name == "apply") Summary(pots)
+            else if (name == "tupled") Summary(pot1)
             else if (name == "curried") {
               val arity = defn.functionArity(sym.info.finalResultType)
-              val pots = (1 until arity).foldLeft(Set(pot1)) { (acc, i) =>
-                Set(Fun(acc, Effects.empty)(pot1.source))
+              val pots = (1 until arity).foldLeft(Vector(pot1)) { (acc, i) =>
+                Vector(Fun(acc, Effects.empty)(pot1.source))
               }
-              Summary(pots, Effects.empty)
+              Summary(pots)
             }
             else Summary.empty
 

compiler/src/dotty/tools/dotc/transform/init/Effects.scala

@@ -12,8 +12,8 @@ import core.Contexts._
 import Potentials._
 
 object Effects {
-  type Effects = Set[Effect]
-  val empty: Effects = Set.empty
+  type Effects = Vector[Effect]
+  val empty: Effects = Vector.empty
 
   def show(effs: Effects)(using Context): String =
     effs.map(_.show).mkString(", ")
@@ -25,6 +25,8 @@ object Effects {
     def show(using Context): String
 
     def source: Tree
+
+    def toEffs: Effects = Vector(this)
   }
 
   /** An effect means that a value that's possibly under initialization
@@ -58,8 +60,6 @@ object Effects {
 
   // ------------------ operations on effects ------------------
 
-  extension (eff: Effect) def toEffs: Effects = Effects.empty + eff
-
   def asSeenFrom(eff: Effect, thisValue: Potential)(implicit env: Env): Effect =
     trace(eff.show + " asSeenFrom " + thisValue.show + ", current = " + currentClass.show, init, _.asInstanceOf[Effect].show) { eff match {
       case Promote(pot) =>

compiler/src/dotty/tools/dotc/transform/init/Potentials.scala

@@ -15,8 +15,8 @@ import Types._, Symbols._, Contexts._
 import Effects._, Summary._
 
 object Potentials {
-  type Potentials = Set[Potential]
-  val empty: Potentials = Set.empty
+  type Potentials = Vector[Potential]
+  val empty: Potentials = Vector.empty
 
   def show(pots: Potentials)(using Context): String =
     pots.map(_.show).mkString(", ")
@@ -31,6 +31,8 @@ object Potentials {
 
     def show(using Context): String
     def source: Tree
+
+    def toPots: Potentials = Vector(this)
   }
 
   sealed trait Refinable extends Potential {
@@ -153,8 +155,6 @@ object Potentials {
 
   // ------------------ operations on potentials ------------------
 
-  extension (pot: Potential) def toPots: Potentials = Potentials.empty + pot
-
   /** Selection on a set of potentials
    *
    *  @param ignoreSelectEffect Where selection effects should be ignored

compiler/src/dotty/tools/dotc/transform/init/Summarization.scala

@@ -304,7 +304,7 @@ object Summarization {
       def parentArgEffsWithInit(stats: List[Tree], ctor: Symbol, source: Tree): Effects =
         val init =
           if env.canIgnoreMethod(ctor) then Effects.empty
-          else Effects.empty + MethodCall(ThisRef()(source), ctor)(source)
+          else Effects.empty :+ MethodCall(ThisRef()(source), ctor)(source)
         stats.foldLeft(init) { (acc, stat) =>
           val summary = Summarization.analyze(stat)
           acc ++ summary.effs
@@ -334,7 +334,7 @@ object Summarization {
                 if tref.prefix == NoPrefix then Effects.empty
                 else Summarization.analyze(tref.prefix, ref).effs
 
-              prefixEff +  MethodCall(ThisRef()(ref), ctor)(ref)
+              prefixEff :+ MethodCall(ThisRef()(ref), ctor)(ref)
             }
         })
       }

compiler/src/dotty/tools/dotc/transform/init/Summary.scala

@@ -18,10 +18,10 @@ case class Summary(pots: Potentials, effs: Effects) {
     Summary(pots ++ summary2.pots, this.effs ++ summary2.effs)
 
   def +(pot: Potential): Summary =
-    Summary(pots + pot, effs)
+    Summary(pots :+ pot, effs)
 
   def +(eff: Effect): Summary =
-    Summary(pots, effs + eff)
+    Summary(pots, effs :+ eff)
 
   def dropPotentials: Summary =
     Summary(Potentials.empty, effs)
@@ -44,14 +44,14 @@ case class Summary(pots: Potentials, effs: Effects) {
 object Summary {
   val empty: Summary = Summary(Potentials.empty, Effects.empty)
 
-  def apply(pots: Potentials): Summary = new Summary(pots, Effects.empty)
+  def apply(pots: Potentials): Summary = empty ++ pots
 
   @targetName("withEffects")
-  def apply(effs: Effects): Summary = new Summary(Potentials.empty, effs)
+  def apply(effs: Effects): Summary = empty ++ effs
 
-  def apply(pot: Potential): Summary = new Summary(Potentials.empty + pot, Effects.empty)
+  def apply(pot: Potential): Summary = empty + pot
 
-  def apply(eff: Effect): Summary = new Summary(Potentials.empty, Effects.empty + eff)
+  def apply(eff: Effect): Summary = empty + eff
 }
 
 /** Summary of class.